According to a recent study, the United States is home to about one in every three ultra-high net worth individuals — those with $30 million or more in total assets. At last count, 65,000 U.S. residents possess more than $9 trillion.

Earlier this week, wealth research group Wealth-X and UBS released their World Ultra Wealth Report for 2013, a comprehensive analysis of the global ultra-high net worth population. Based on that report, 24/7 Wall St. identified the 10 nations with the most ultra-wealthy residents. These are the nations with the most multimillionaires.

Most of the nations where the ultra-wealthy live are themselves rich. Of the 10 countries with the largest ultra-high net worth populations, seven have a per capita gross domestic product of $35,000 and are among the top 25 nations in the world by that measure. The U.S. had an estimated per capita GDP of $49,922 as of 2012.

The majority of these nations have large populations. China and India each have more than 1.2 billion inhabitants. Brazil, Japan and the U.S., which all are among the top ten for most multimillionaires, each have more than 100 million residents

Most of the countries on this list also have large economies. This creates opportunities for residents to sell new products on a large scale, either abroad or to well-off local consumers. Four of the top five nations for ultra-high net worth individuals are among the top five nations for overall GDP. The U.S. is the world’s largest economy, with a GDP of nearly $16 billion in 2012.

Many of these countries have highly advanced economies. Germany, Switzerland and the U.S. are considered to be among the most developed and internationally competitive countries in the world. In these markets, new innovations or other productive contributions to the economy can lead to wealth.

Conversely, Brazil, China and India are considered to be emerging markets, where the potential for economic growth is potentially very high. These three countries, along with Russia, are often called the “BRIC” nations and are expected to emerge as key-players in the global economy in the near future.

To determine the nations with the most multimillionaires, 24/7 Wall St. reviewed the Wealth-X and UBS World Ultra Wealth Report for 2013. According to the report, which identified the countries with the most ultra-high net worth residents, ultra-high net worth requires at least $30 million in assets. In addition, we used per capita GDP figures from the International Monetary Fund’s (IMF) World Economic Outlook table and GDP figures from the CIA’s World Factbook. Both measures are adjusted to reflect purchasing power parity exchange rates. Additional figures on population are also from the World Factbook. Some GDP and and population figures for 2012 are estimates.

These are the 10 countries with the most multimillionaires.